This invention relates to a novel monomeric and polymeric compounds and to methods for their preparation. In a more specific aspect, this invention relates to polyaromatic ether-sulfone-ketones with fluorinated-p-cyclophane units as cross-linking sites and to a novel fluorinated-p-cyclophane bis-acid chloride monomer utilized in the preparation of the polyaromatic ether-sulfone-ketones.
In order to prepare thermally stable laminating resins, recent research efforts have concentrated on developing new processes for the cross-linking of resins without liberating undesireable gaseous side products. The synthesis of linear polymers incorporating internal p-cyclophane units and the cross-linking of these polymers by heating above 250.degree. C. has been accomplished heretofore by Myers et al as reported in R. Z. Myers, J. W. Hamersma and H. S. Green, J. Polym. Sci., B, 10, 685 (1972).
Cross-linking in such polymers is effected by the thermal homolysis of the dimethylene bridge in the highly strained p-cyclophane system to form 4,4'-ethylenedibenzyl diradicals (II). In the absence of free radical traps, these radicals may either recombine intramolecularly to regenerate (I), or may react intermolecularly across polymer chains to give rise to ethylenic cross-links. ##STR1##
Earlier publications, such as K. P. Sivaramakrishnan, C. Samyn, I. J. Westerman, D. T. Wong and C. S. Marvel, J. Polym. Sci, Polym. Chem. Ed., 13, 2507 (1975), have disclosed that some dozen polymers containing p-cyclophane were prepared and were thermally stable laminates. As early as 1933, the unusual properties of polytetrafluoroethylene (Teflon) were observed and the interest in the synthesis of polymers fluorine increased greatly thereafter.
As a consequence, a considerable research effort has been generated in an attempt to provide new and useful fluoro-substituted polymers. The results of that research effort have culminated in the development of a novel monomeric acid chloride as well as the preparation of novel polymeric compounds resulting from the use of that novel monomer as a cross-linking site. Instead of using simple-p-cyclophane units, the present invention unexpectedly discovered that two fluorine substituted p-cyclophanes, one of which is novel, could be incorporated as cross-linking sites along the polymer chain. The resulting polymers are excellent film-formers and, in addition, form excellent glass fiber laminates characterized by excellent thermal stability.